In reality, London is a collection of neighbourhoods and villages stitched together by buses, trains, trams, and of course, the Underground.
If you're caught working without the correct visa, you'll likely be removed from the country and you could barred from re-entering the UK for up to 10 years.
This can be seen in the growing popularity of the United Kingdom Independence Party (UKIP) and fringe groups such as the English Defence League (EDL) and British National Party (BNP).
Even the ruling Conservative Party has pledged Thus, coming to work in the UK is likely to become even more difficult in the years to come.
Though I've never had anyone complain to my face about me being an immigrant, I have been involved in a couple of conversations where people complain about immigrants/immigration/foreigners in general.
When I've pointed out to them that I'm also a foreigner, they generally say something along the lines of Still, in my experience, this is an extremely rare conversation to have and it's one that you could have anywhere.
Postcodes are a common way to identify roughly where you live and they correspond very loosely with compass points from the City of London.